A high pulsed magnetic field measurement system based on the use of CMR-B-scalar sensors was developed for the investigations of the electrodynamic processes in electromagnetic launchers. The system consists of four independent modules (channels) which are controlled by a personal computer. Each channel is equipped with a CMR-B-scalar sensor connected to the measurement device-B-scalar meter. The system is able to measure the magnitude of pulsed magnetic fields from 0.3 T to 20 T in the range from DC up to 20 kHz independently of the magnetic field direction. The measurement equipment circuit is electrically separated from the ground and shielded against low and high frequency electromagnetic noise. The B-scalar meters can be operated in the presence of ambient pulsed magnetic fields with amplitudes up to 0.2 T and frequencies higher than 1 kHz. The recorded signals can be transmitted to a personal computer in a distance of 25 m by means of a fiber optic link. The system was tested using the electromagnetic railgun RAFIRA installed at the French-German Research Institute of Saint-Louis, France.

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The permeability of the yeast cells (Saccharomyces cerevisiae) to lipophilic tetraphenylphosphonium cations (TPP(+) ) after their treatment with single square-shaped strong electric field pulses was analyzed. Pulsed electric fields (PEF) with durations from 5 to 150 µs and strengths from 0 to 10 kV/cm were applied to a standard electroporation cuvette filled with the appropriate buffer. The TPP(+) absorption process was analyzed using an ion selective microelectrode (ISE) and the plasma membrane permeability was determined by measurements obtained using a calcein blue dye release assay. The viability of the yeast and the inactivation of the cells were determined using the optical absorbance method. The experimental data taken after yeasts were treated with PEF and incubated for 3 min showed an increased uptake of TPP(+) by the yeast. This process can be controlled by setting the amplitude and pulse duration of the applied PEF. The kinetics of the TPP(+) absorption process is described using the second order absolute rate equation. It was concluded that the changes of the charge on the yeast cell wall, which is the main barrier for TPP(+) , is due to the poration of the plasma membrane. The applicability of the TPP(+) absorption measurements for the analysis of yeast cells electroporation process is also discussed.

The magnetoresistance (MR), sheet resistance (R ), and structure of vacuum-deposited thin bismuth films with 0.3 to 1.5 µm thickness prepared on noncrystalline dielectric amorphous substrate were investigated as a function of substrate (TS) and annealing (TA) temperatures. The investigations were mainly focused on films prepared at critical TS and TA temperatures, at which essential changes in film structure and magnetoresistance value were obtained. The existence of these temperatures is associated with the intensive growth of high-quality crystallites. The mechanism of this phenomenon is discussed. In the case of annealed 1-1.5 µm thick films, the size of these crystallites ranges from 50 to 200 µm. It was demonstrated that such films have large transverse magnetoresistance ranging up to 170% for 1.5 µm thick films at 293 K in 2.5 T magnetic fields.

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In this research we have evaluated the binding kinetics between an immobilized receptor and several genetically engineered ligands, differing by molecular mass or by the number of binding sites available for the binding to the receptor. Genetically engineered protein (GCSF-Receptor), which contains some antibody parts (Fc domain) and at some extent is similar to antibody because also has two binding sites that selectively bind another proteinglycoprotein granulocyte colony stimulating factor (GCSF), which was immobilized on a thin gold layer in order to design an immunosensor sensitive to GCSF. Three structurally different GCSF-based proteins were genetically-engineered and evaluated as ligands, which selectively bind to immobilized GCSF-Receptor: (i) GCSF monomer (mGCSF), (ii) GCSF-homodimer consisting of two via polypeptide Lα-based linker 'fused' GCSF molecules ((GCSF)2Lα) and (iii) GCSFheterodimer (SCF-Lα-GCSF), which is based on a native GCSF molecule 'fused' via Lα-based linker with another proteina soluble part of stem cell factor (SCF). SCF, unlike GCSF, does not contain any site suitable for GCSF-Receptor binding. The ligands differ by: (i) molecular mass -(GCSF)2Lα and SCF-Lα-GCSF F are two times heavier than mGCS, (ii) number of binding sites -mGCSF and SCF-Lα-GCSF have one binding site, while (GCSF)2Lα has two. The binding kinetics of mGCSF, (GCSF)2Lα, and SCF-Lα-GCSF with immobilized GCSF-Receptor was investigated using total internal reflection ellipsometry. The interaction kinetics of the mGCSF and SCF-Lα-GCSF are both well described using a standard Langmuir kinetics model. However, receptor-ligand association and dissociation rates in the case of SCF-Lα-GCSF ligand are about 10 times lower than that of mGCSF. The association rate of (GCSF)2Lα

An investigation of the yeast cell resealing process was performed by studying the absorption of the tetraphenylphosphonium (TPP+) ion by the yeast Saccharomyces cerevisiae. It was shown that the main barrier for the uptake of such TPP+ ions is the cell wall. An increased rate of TPP+ absorption after treatment of such cells with a pulsed electric field (PEF) was observed only in intact cells, but not in spheroplasts. The investigation of the uptake of TPP+ in PEF treated cells exposed to TPP+ for different time intervals also showed the dependence of the absorption rate on the PEF strength. The modelling of the TPP+ uptake recovery has also shown that the characteristic decay time of the non-equilibrium (PEF induced) pores was approximately a few tens of seconds and this did not depend on the PEF strength. A further investigation of such cell membrane recovery process using a florescent SYTOX Green nucleic acid stain dye also showed that such membrane resealing takes place over a time that is like that occurring in the cell wall. It was thus concluded that the similar characteristic lifetimes of the non-equilibrium pores in the cell wall and membrane after exposure  to  PEF indicate a strong coupling between these parts of the cell.

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